Image sensors have become ubiquitous. They are widely used in digital still cameras, cellular phones, security cameras, as well as, medical, automobile, and other applications. The technology used to manufacture image sensors has continued to advance at a great pace. For example, the demands of higher resolution and lower power consumption have encouraged the further miniaturization and integration of these devices.
High dynamic range (HDR) refers to techniques used to expand the range of luminosity in cameras/image sensors. One goal is to have the camera capture a similar rage of luminance as the human eye typically sees. HDR cameras can display a greater range of luminance levels than cameras using more traditional methods. This is most evident in photography of image scenes containing very bright light contrasted with extreme shade or darkness.
However, despite the advent of HDR imaging, there is still room for improvement in the image sensor field. Higher resolution HDR images are desirable in many applications. Advances in image sensor technologies allow for other technological spaces to grow in parallel (e.g., self-driving cars which are reliant on the quality of images received to make informed driving decisions).
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.